1. Field of the Invention
The present invention relates to a cartridge changing apparatus in use for a continuous play-back apparatus which contains a plurality of discs which are continuously played back.
2. Description of the Prior Art
FIG. 30 is a drawing showing the construction of a conventional automatic changing apparatus for exchanging a plurality of cartridges, disclosed in Japanese Utility Model Laid-Open No. 64-56055.
According to this utility model, a plurality of holders 1 are provided and a catcher 2 selectively grips one of them. Then, the selected holder 1 is extracted from a guide means and a loading arm 3 is operated to move the catcher 2 and the holder 1. After this, the cartridge is set on a tape running system.
FIG. 31 is a drawing for showing an example of part of a conventional cartridge changing apparatus for a plurality of cartridges. As shown in the same Figure, in the construction which enables selection of all cartridges at the insertion position, a guide 4 needs a space channel 6 in which a pin 5 of the holder 1 can be inserted above the uppermost stage and below the bottommost stage and, therefore, the guide 4 needs to be extended vertically by the amount required by the additional channel length. Therefore, the problem of this conventional cartridge changing apparatus is that it is difficult to reduce the size thereof.
Thus, such a construction wherein both the upper guide 7 and the lower guide 8 are divided to a cartridge insertion section and a cartridge play-back section while the cartridge insertion section and the cartridge play-back section are provided with channels the end of which are open as shown in FIG. 32 can be considered. However, the guides 7 and 8 of the play-back section need to be formed so as to be as small and thin as possible in order to secure vibration permissible distance between the cartridge play-back section and the other part, for example, an elevator. According to this design, this kind of the guide part cannot be produced from the viewpoint of the strength and precision, or otherwise the production cost thereof is increased.
Thus, a method wherein the lower guide 9 is mounted on a floating deck and the upper guide 10 is placed on the elevator 11 which is moved vertically can be considered, as shown in FIG. 33. Even when this construction is used, if reduction of the size of the mechanism is intended while a specified vibration permissible distance for the floating deck is secured, it is difficult to secure vibration permissible distance between the holder clamp member 12 and the holder pin 5. In these conventional cartridge changing apparatus, the carrier mechanisms are complicated. Thus, the construction attached to this mechanism becomes complicated, so that the number of required parts increases.